A border on the small ones in the same color won't detract from the border on the edge. However, try blocking them first. If they are close enough to the same size then you don't need to worry about it.

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Jan

When asking questions ALWAYS post the name and a link for the pattern if you have it.

I'd wash/block both squares first and try to squish (or pull) them into shape. After all, washing and blocking that small of an object won't take long and what do you have to lose? Then if that doesn't work, reknitting might be the way to go.

Be sure to let both squares dry completely, though, and see how well they keep their shape.

You know, it's always great to ask questions, but you can try some of this stuff out on your own, too. Different yarns behave differently and you won't know the end result (and whether you're happy with it) unless you try it. Go for it!

Odds are they'll be OK like that. Garter stitch is pretty forgiving. I don't think there's enough difference to be worth putting a row of single crochet around the small ones.
Try putting a couple together and see whether you mind the difference; if you do, you can always re-knit the small ones, and if you don't see enough difference to be a problem, you have part of the seaming done!